The present invention relates to novel pyrimidine derivatives useful as carcinostatic substances. More particularly, the invention relates to 1-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4-carbonitrile and a method for its preparation.
In recent years, a number of carcinostatic substances for use in chemotherapy against cancers have been developed and proposed. Among others, various derivatives of pyrimidine or purine are known to have anti-carcinogenic activites and antagonize the pyrimidine or purine metabolism pertaining to nucleic acid synthesis. However, the use of these carcinostatic substances has thus far served merely as a measure auxiliary in conjunction with surgical operations to resect cancer cells and their peripheral tissues, or radiotherapy to destroy cancer cells.
The local cancer cells, though resected by surgical operations, are within the bounds of possibility of metastasizing to other parts of the body and, once such metastasis has taken place throughout the body, a complete cure of the cancer will hardly be expected by the local resection. Therefore, the general and main therapeutic means to cure cancers is chemotherapy whereby the growth of the cancer cells is prevented by the action of suitable carcinostatic substances. For the purpose, the development of substances having excellent anti-carcinogenic activities and useful in the chemotherapy of cancers has been eagerly desired.